含瓦斯煤三轴应力加载实验设计与实践  

Experimental design and practice of triaxial stress loading on the gas-containing coal

作　　者：郭海军 吴海楠 于英杰 王凯[1] 徐超[1] 周爱桃[1] 佟瑞鹏[1] GUO Haijun;WU Hainan;YU Yingjie;WANG Kai;XU Chao;ZHOU Aitao;TONG Ruipeng(School of Emergency Management and Safety Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China)

机构地区：[1]中国矿业大学(北京)应急管理与安全工程学院,北京100083

出　　处：《实验技术与管理》2025年第1期231-237,共7页Experimental Technology and Management

基　　金：全国煤炭行业高等教育教学改革研究课题(2021MXJG128);中国矿业大学(北京)2024年研究生教育教学改革项目(YJG2024003);中国矿业大学(北京)课程思政示范课程建设项目(SZ240201)。

摘　　要：利用自主研发的煤体“吸附-力学-渗流”耦合特性测试系统,实验研究了瓦斯对煤体强度和吸附膨胀变形特征的影响,设计了不同围压和瓦斯压力条件下的三轴加载实验。实验结果显示,瓦斯显著削弱了煤体的强度,其中游离瓦斯的影响大于吸附瓦斯。煤体强度的削弱程度与瓦斯压力呈正相关关系,而围压变化对其影响较小。另外,通过对比分析发现,实验室实验法测得的含瓦斯煤体体积应变比理论计算法更为准确。实验室实验法能够为确定煤基质的吸附膨胀最大应变和吸附变形朗格缪尔压力提供可靠依据。[Objective]To reflect a more similar original stress environment and to make the research on the influence of gas on the mechanical properties of coal bodies in the coal mining process more convincing,a triaxial stress loading experiment on gas-containing coal is introduced.On the one hand,the experimental teaching scheme for studying the strength and deformation characteristics of coal based on the triaxial stress loading experiment can be concretized.On the other hand,it can be helpful for students to understand the mechanical characteristics and adsorption deformation characteristics of gas-containing coal,which lays a foundation for subsequent in-depth research.[Methods]In this study,with the help of a coupling instrument to measure the adsorption,mechanics,and seepage characteristics of coal,the actual stress environment of coal is simulated by adjusting the loading module and the triaxial stress loading experiment on coal under different confining stress and gas pressure conditions is carried out.Among them,the magnitude of the axial stress and confining stress applied to the coal body can be achieved accurately by adjusting the hydraulic pump,and the required gas pressure can be achieved by adjusting the valve of the gas cylinder.First,the coal samples are sealed in the equipment,and the confining stress and gas pressure are adjusted to the target values.Second,the axial stress is continuously loaded until the coal body is damaged.Finally,according to the automatically recorded full stress-strain curves of coal samples,the specific values of peak stress,axial strain,radial strain,and volumetric strain of coal under different initial conditions can be obtained.Then,the maximum and minimum principal stress values under different stress conditions are plotted in a Cartesian coordinate system and fitted using the Mohr-Coulomb formula,and the cohesive force and internal friction angle of coal samples can be calculated.In addition,the weakening law of the free gas and adsorbed gas on the strength of the coal bod

关 键 词：三轴应力加载 含瓦斯煤 力学特征 吸附变形特性 实践教学 

分 类 号：X932[环境科学与工程—安全科学]